Members of the Physical Sciences Laboratory provide consulting services to the scientists and physicians at NIH in the areas of applied mathematics, statistics, and the physical sciences. A continuing project is the construction and querying of a large data base on head injured veterans of Vietnam. We have also developed an error theory for interpolation in computerized tomography. In a third project we have developed an accurate approximate solution to the generalized birthday problem, a classical problem in probability, with application to a genetic assay.